Posted: 6/5/2002 2:59:07 PM EDT
I've been looking at buying a generator for emergency power. I tried a search on harborfreight.com and now I'm overloaded with info. I'm thinking 5KW would be enough for emergency use. What do you guys think?
Any recommendations on brand, gasoline vs propane, etc?
If you intend to run a well pump inaddition to refrigeration, lights, etc you will be better off with a 7.5 Kw set. If you heat your home with fuel oil, you should consider a diesel genset. Although MUCH more expensive, diesel engines will run on home heating oil which is essentially the same thing. This will ensure you a large fuel supply and some degree of portability. Most gasoline engine generators are made for intermittient use like a power saw or other on-off appliance. Long runs under load will wipe out a cheap gasoline generator in short order.
OT: I would also put some kind of fuel preservative to prevent fuel break down. I've been using Gasoline or Disel PRG from Major Surplus N Survival, but you should check to see if you can find it locally in your area.
The advantage to propane is that it doesn't go bad after being stored for several years. Also, it's very clean-burning, which minimizes concerns about exhaust fumes, and allows you to run longer between oil changes.
Natural gas is a dubious choice, since it's no more reliable than utility power— In many disasters, you would lose both.
I have worked on construction all my life. The best portable gasoline generator is a HONDA, bar none. However they are very expensive. They run forever and hold their value.
I came home from work and found my power off one day five years ago. I ran out to Sears and bought the best 5KW gas generator they had at that time. Made for Sears by Generac. Circuit breakers, oil filter, and all the bells and whistles. My electricity came on as soon as I went home and has never been off, since then, for more than a few seconds . Go figure.
Warning, be sure to ground the generator when you are hooked up and running. I use a good pair of jumper cables to a grounding rod next to my power service entrance. If you do not have a ground rod buy one from Radio Shack and pound it into the ground and use it.
I have a 30 Amp twistlock connector to feed my air compressor 220 volts. I made a connector with heavy wire to back feed the house from my generator to the electrical panel through the twistlock recptacle.
Most important. You have to turn off the main power from the power company's lines. If the power comes on while you are hooked up and running the generator, it could blow the whole thing up on you.
Transfer switches are getting more popular these days to switch over from generator to Utility power source. Also this will protect electrical workers from being electrocuted by feedback from your generator.
Add up the amp draw from all the appliances you plan to run. Volts X amps = watts. Add up all the watts and get a generator with around 20% more than you estimate.
Also electric motors on refrigerators, furnaces and well pumps have a inrush current on startup that may take you over the generator rating. I plan to turn most everything else off to run any electric motor if I ever have to. Generators having circuit breakers are a plus.
Keep the gas tank empty and a can of gas handy with gas preservative in it. Replace the gas every six month if not used. Change the generator oil every year or sooner if you use it or not.
If you need a whole house , permanently hooked up generator, let a professional contractor install it for you. Get a good gurantee with it.
If you are on a budget I think W.W. Grainger sells them.
Some generators are wired so that the 120 volt output is split between two outlets on two different circuits, limiting the maximum power available on either circuit to approximately half of the generator’s rated capacity. This can be a problem if you only need to power one large load, since it leaves half of the generator’s total capacity unused. Unfortunately, this limitation isn’t always apparent in the generator sales literature.
Some of the newest Honda and Yamaha generators are equipped with "Inverter Technology" that uses a special high-frequency multi-pole alternator in combination with a microcomputer-controlled AC inverter to deliver constant voltage and line frequency regardless of engine speed or electrical load. The alternator used is much smaller and lighter than traditional designs — For example, Honda claims its inverter-equipped EU3000is model is half the size and weight of its conventional EX3300 model, even though both products have identical power output ratings.
Inverter technology allows the alternator to spin at whatever speed provides the greatest efficiency, because the inverter is capable of maintaining a steady voltage, frequency and waveform regardless of alternator speed. So, engine speed can be automatically reduced under lightly-loaded conditions, reducing noise, fuel consumption and exhaust. It's also very clean power.
Some inverter-type generators also include a "strapping" connection that allows two identical models to be connected together, approximately doubling the power available for operating a single load.
One word: [b]HONDA!![/b]
They make great portable gensets.
Here's a quick story for 'ya:
Keep in mind that I built my house right before Y2k was about to strike.... [;)]
I wired the house myself and planned everything with great attention to detail.
My desire was to have independent circuits for most of the key devices that would require emergency power during a commercial power failure.
I purchased a Kohler 15kva natural gas generator w/ an asco automatic transfer switch and had a 4'x8'(x 2'deep) concrete pad poured in my backyard.
After everything was in place, the evil town building inspector made me remove the generator since it posed a "noise abatement" problem for the neighborhood. After having the generator dragged off to avoid further fines, I settled on 2 gasoline operated honda 6.5kw generators w/ a manual transfer switch. A much LOUDER and dangerous solution.
(Lesson Learned?? ----> Vote Republican ! -- or move out of the PRNJ)
Here's a pic of the electrical service and switchgear:
Electric service. The two panels at left are for household circuits.(square d qo / 40 circuits @)
The third panel is dedicated for emergency circuits. (telco room / refrigerator / freezers / outside lights / key lights and receptacles in the house / sump pump / furnace / 1 of the air-conditioning system)
The fourth panel over is the manual generator transfer switch. (Controls only the third panel)
Note the Streamlight Lightbox (orange flashlight) in the lower right-hand corner.
VERY IMPORTANT item !!
It's the "power failure" version and turns on upon losing AC power. It's been a lifesaver and is always ready to go....
Oops.. sorry for the big pic !
One other word of advice -- make sure to stabilize your fuel if you choose a gasoline powered generator.
I keep about 60 gallons on hand and have been very lazy about rotating the stock.
I just filled up my wife's jeep (I experimented on her -- hehehe) with 1999 gasoline treated with PRI-G. It didn't smell "old" or like varnish and the vehicle didn't seem to mind it at all!
(I always thought that stabilizers were a scam. Guess I was wrong !)